title: Ceramic-Ceramic Bearing: Too Unpredictable to Use it Regularly.
abstract: BACKGROUND
  Ceramic-on-ceramic (CoC) bearings have excellent tribologic properties because of the smoothness, hardness, and wettability of the material. Therefore, their use has been proposed in younger, active patients who may wear out a traditional metal-on-polyethylene bearing. The same material properties that are beneficial to tribology may also create problems, however. For example, squeaking and fracture of the bearing materials have been reported to occur.
  
  
  OBJECTIVE
  The purpose of this paper was to investigate the literature reporting the complications of ceramic bearings and attempt to provide insight into their implications.
  
  
  METHODS
  The US National Library of Medicine Database (PubMed) was searched using the terms "ceramic-ceramic total hip replacement," "complications," "squeaking," and "fracture." Only clinical studies with a clear reporting of the incidence of these complications were included.
  
  
  RESULTS
  The literature reports that squeaking of the CoC bearing occurs in a certain percentage of patients and is likely indicative of edge loading and excessive wear. Other factors, such as patient height, weight, range of motion, and implant design, may contribute to the propensity for squeaking. Fracture is a unique risk of the CoC articulation that requires revision surgery. Though improvements in manufacturing techniques have reduced the fracture risk to a very low percentage, the ceramic material remains susceptible to this complication by impingement and component malposition.
  
  
  CONCLUSIONS
  Because of these possible negative outcomes associated with the ceramic material, the CoC bearing is too unpredictable to use regularly, and its use should be limited to patients who would benefit the most from it.
authors.affiliation: Clinical Orthopaedic Surgery, Weill Cornell Medical College, New York, NY 10065 USA ; Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021 USA.
authors.forename: Edwin P
authors.initials: EP
authors.lastname: Su
keywords: bearing surfaces; ceramic; complications; squeaking; total hip arthroplasty